Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!udel!haven!wam!walrus
From: walrus@wam.umd.edu (Udo K Schuermann)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Fast circles?
Keywords: Circles, fast, Blitter
Message-ID: <1990Dec21.041242.16122@wam.umd.edu>
Date: 21 Dec 90 04:12:42 GMT
References: <656@cbmger.UUCP>
Sender: usenet@wam.umd.edu (USENET Posting)
Reply-To: walrus@wam.umd.edu (Udo K Schuermann)
Organization: University of Maryland at College Park
Lines: 43

In article <656@cbmger.UUCP> peterk@cbmger.UUCP (Peter Kittel GERMANY) writes:
>
>Here a question for a little project I perhaps would like to
>continue during the holidays:
>
>I want to draw FAST, filled circles in arbitrary size and in
>arbitrary (but solid) color on a 4-bitplane hires screen.
>You see, I still love these first-day Caleidoscope demos and
>want to do similar things on my own.

> [stuff deleted]

Before I had a chance to fix Kaleidoscope (Polyscope?) to run entirely
in Chip RAM (and make it harddisk installable) I had a few neat
crashes that left me with a brown screen and a bunch of circles in
different sizes and colors drawn on it, in a grid pattern.  From this
I assume that EA pre-draws these items on a screen in the background,
then uses the blitter to transfer different sizes and colors from one
screen to another.  I don't know if they're using more than one screen
to store different colors, sizes, etc.
	Btw: my copy of PolyScope runs on a 5 Meg 68030, off the HD.
It won't exit, but it will run.  It's faster, too :-)  Polyscope on
caffeine.

>5. Would it be necessary to turn to assembler to gain further
>   performance?

Can't hurt if you do that in time-critical places, but it shouldn't be
necessary.  PolyScope is written in C (at least there are %ld in the
debugging statements of the code).  Try it in C first, then find out
where the bottle-necks are.  Optimize those with assembler.

>Have a nice Christmas and a happy plus successfull new year!

And the same to you!

>Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
>Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk

Cheers!

 ._.  Udo Schuermann        "How is American beer similar to making love in
 ( )  walrus@wam.umd.edu    a canoe?" -- "Both are f***ing close to water."